Temperature Equilibration due to Charge State Fluctuations in Dense Plasmas

The charge states of ions in dense plasmas fluctuate due to collisional ionization and recombination.  As these fluctuations modify the ion interaction potential, over a cycle of ionization and recombination they can lead to an exchange of energy between the ions and free electrons.

 

In this work, we develop a theory for electron-ion energy transfer due to charge state fluctuations. Combining the theory with a random walk approach for the fluctuations, we present calculations for experimentally accessible plasmas. We find that the energy exchange rate from this novel mechanism could be comparable to, or even exceed, the rate due to direct electron-ion collisions. Furthermore, this mechanism is predicted to exhibit a complex dependence on the temperature and ionization state of the plasma. This could contribute to our understanding of significant variation in experimental measurements of equilibration times.